Explanation:
The beautiful
Trifid Nebula
is a cosmic study in colorful contrasts.
Also known as M20, it lies about
5,000
light-years away toward the
nebula rich
constellation Sagittarius.
A star forming region in the plane of our galaxy,
the Trifid illustrates three different types of
astronomical nebulae;
red emission nebulae dominated by
light emitted by hydrogen atoms,
blue reflection nebulae produced
by dust reflecting starlight, and
dark nebulae where
dense dust clouds appear in silhouette.
The bright red emission region, roughly separated into three
parts by obscuring, dark dust lanes, lends the Trifid its popular name.
In this
well met scene, the red emission is also juxtaposed with
the telltale blue haze of reflection nebulae.
Pillars and jets sculpted by
newborn stars, below and left of the emission nebula's center, appear
in Hubble Space Telescope close-up images
of the region.
The Trifid Nebula is about 40 light-years across.